What is the CVSS score of CVE-2020-13556?

CVE-2020-13556 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 4.5%.

Is there a public PoC exploit available for CVE-2020-13556?

Yes, a public proof-of-concept exploit is available for CVE-2020-13556. Prioritise patching immediately. EPSS: 4.5%.

Opener CVE-2020-13556

CRITICAL

Out-of-bounds Write (CWE-787)

2020-12-11 talos-cna@cisco.com

Buffer Overflow RCE Memory Corruption Opener

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Dec 11, 2020 - 04:15 nvd

CRITICAL 9.8

DescriptionNVD

An out-of-bounds write vulnerability exists in the Ethernet/IP server functionality of EIP Stack Group OpENer 2.3 and development commit 8c73bf3. A specially crafted series of network requests can lead to remote code execution. An attacker can send a sequence of requests to trigger this vulnerability.

AnalysisAI

An out-of-bounds write vulnerability exists in the Ethernet/IP server functionality of EIP Stack Group OpENer 2.3 and development commit 8c73bf3. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified as Out-of-bounds Write (CWE-787), which allows attackers to write data beyond allocated buffer boundaries leading to code execution or crashes. An out-of-bounds write vulnerability exists in the Ethernet/IP server functionality of EIP Stack Group OpENer 2.3 and development commit 8c73bf3. A specially crafted series of network requests can lead to remote code execution. An attacker can send a sequence of requests to trigger this vulnerability. Affected products include: Opener Project Opener.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate write boundaries, use memory-safe languages, enable compiler protections (ASLR, stack canaries).